NOAA Technical Report NMFS 110

The Distribution of

Kemp's Ridley Sea Turtles

(Lepidochelys kempi) Along the

Texas Coast: An Atlas

Sharon A. Manzella

Jo A. Williams

u.S. Department of Commerce

May 1992
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NOAA Technical Report NMFS 110

The Distribution of Kemp's Ridley Sea

Turtles (Lepidochelys kempi) Along the

Texas Coast: An Atlas

Sharon A. Manzella

J0 A. Williams

May 1992

U.S. DEPARTMENT OF COMMERCE

Barbara Hackman Franklin, Secretary

National Oceanic and Atmospheric Administration

John A. Knauss, Under Secretary for Oceans and Atmosphere

National Marine Fisheries Service

William W. FoxJr., Assistant Administrator for Fisheries
The National Marine Fisheries Service (NMFS) does not approve, recommend or endorse any proprietary product or proprietary material mentioned in this publication. No reference

shall be made tu NMFS, ur to this publication hlrnished by

NMFS, in any advertising or sales prumution which would indicate or imply that NMFS approves, recommends or endorses

any proprietary pruduct or proprietary material mentioned

herein, or which ha., as its purpose an intent to cause directly

or indirectly the advertised product tu be used ur purchased

because uf this NMFS publicatiun.

11
The Distribution of Kemp's Ridley Sea Turtles (Lepidochelys kempi)

Along the Texas Coast: An Atlas

SHARON A. MANZELLA

JO A. WILLIAMS

National Marine Fisheries Service

Southeast Fisheries Science Center

Galveston Laboratory

4700 Avenue U, Galveston, Texas 77551

ABSTRACT

Eight hundred sixty-five records of Kemp's ridley sea turtles (Lepidochelys kempi) reported from Texas between the late 1940's to April 1990 were compiled from six data

bases and the literature, then plotted on a series of Texas maps. Four categories of

Kemp's ridleys are identified throughout the atlas: head-started (turtles that are raised in

captivity their first year of life), wild, historical (pre-1980), and nesters. Geographic,

seasonal, and size distributions of the turtle categories are plotted by regions. Most

Kemp's ridleys were reported from the northeast and central Texas coast. They were

reported from both inshore (landward of barrier islands) and offshore (seaward of barrier islands). Scattered nestings occurred in the central to southern regions. Kemp's

ridleys were found more often during the spring and summer. A total of 546 turtle

records contained measurements; most were 20-59.9 cm curved carapace length and

considered sub-adults. Comparison of distributions of head-started and wild Kemp's ridleys suggests head-started Kemp's ridleys inhabit the same areas as wild Kemp's ridleys.

Introduction _

The Kemp's ridley sea turtle (Lepidochelys kempi) has a

unique life history that has been widely discussed by

sea turtle biologists (Carr 1955, 1957; Carr and

Caldwell 1958; Carr 1961; Hildebrand 1963; Chavez

et al. 1968; Pritchard and Marquez 1973). It is an

endangered species of sea turtle and has the most

restricted breeding range. The primary nesting site for

the Kemp's ridley is on the northeastern coast of

Mexico, near the village of Rancho Nuevo, Tamaulipas,

approximately 322 km (200 mi) south of Brownsville,

Texas (Hildebrand 1963). Scattered nestings occur to

the south and north of the main nesting beach on

the Mexican coast and along the southern and central coastline of Texas (Werler 1951; Carr 1961;

Hildebrand 1963, 1980; Pritchard and Marquez 1973;

Fuller 1978; Francis 1978; Shaver et al. 1988). There

is one record of a Kemp's ridley nesting on the west

coast of Florida (Meylan et al. 1990).

Outside the breeding area, the Kemp's ridley range

includes other coastal areas of the Gulf of Mexico,

the western North Atlantic from Florida to Nova

Scotia and the eastern North Atlantic including the

British Isles, Netherlands, and France (Bleakney

1965; Brongersma 1972; Pritchard and Marquez

1973; Manzella et al. 1988). Brongersma and Carr

(1983) reported one Kemp's ridley from Malta in the

Mediterranean, and two have been reported from

the Madeira Islands and Western Mrica (Brongersma

1972; Fontaine et al. 1989a).

In 1978 an experimental sea turtle head-start conservation project began, involving the U.S. Fish and

Wildlife Service, National Park Service, National Marine Fisheries Service (NMFS), and Texas Parks and

Wildlife Department, in co-operation with the

Instituto acional de la Pesca of Mexico. The objective of this project was to increase survival during the

first year of life and to establish a nesting colony of

Kemp's ridleys on Padre Island National Seashore

(PINS), near Corpus Christi, Texas. Annually, 2000

eggs were removed from the natural nesting beach

and were incubated in Padre Island sand at PINS.

Mter hatching, the turtles were allowed to crawl

down the beach to the water and swim in the surf

(Fletcher 1989). This "imprinting" to Padre Island
2 NOAA Technical Report NMFS 110

sand and surf was undertaken in hopes that the

turtles would return there to nest when mature. After

capturing the hatchlings from the surf they were

transferred to NMFS Galveston Laboratory.

In 1988 the practice of "imprinting" was abandoned and hatchlings were transferred to Galveston

directly from the nesting beach in Mexico (Fontaine

et al. 1990). The turtles were reared in captivity for

9-11 months, then tagged and released into the Gulf

of Mexico (Fontaine et al. 1989b). The head-start

project is ongoing and as of May 1991, 16,590 headstarted Kemp's ridleys have been released. To date,

no head-started Kemp's ridley has been positively

identified, through the presence of tags, nesting on

the beaches of Texas or Mexico.

In 1989 a panel of sea turtle experts reviewed the

head-start project and recommended criteria for assessing success of head-starting (Wibbels et al. 1989).

Some of the recommended criteria were 1) apparent

competence of head-started turtles at and after release (i.e., whether or not head-started turtles survive

and grow in the wild, and whether they are comparable to wild ridleys in body weight, feeding behavior,

orientation, and reactions), 2) comparison of recovery locations of head-started and wild ridleys.

The present atlas addresses these criteria by comparing and illustrating the geographic, seasonal, and

size distributions of head-started and wild Kemp's ridleys found along the Texas coast.

Methods _

The atlas' data cover the late 1940's through April

1990 when 865 Kemp's ridley records were compiled

from six data bases and literature. The 865 records

represent an up- to-date documentation of Kemp's

ridley occurrence along the Texas coast. Most records

probably resulted from opportunistic events rather

than structured sampling schemes. Prior to 1980

and the establishment of the Sea Turtle Stranding

and Salvage Network (STSSN), no organized collection of sea turtle information was available. With

the STSSN, a more concerted effort was started to

document the occurrence of sea turtles along the

southeast coast of the United States. But even after

1980, most records probably resulted from opportunistic reports from the general public. Since 1986,

as part of the STSSN, systematic surveys to locate

stranded sea turtles have been conducted along the

Texas coast (Heinly et al. 1988; Duronslet et al.

1991). It is not known, however, whether more

stranded sea turtles were documented as a result of

these surveys.

Records of 506 turtles were obtained from the

STSSN data base maintained at the NMFS Southeast

Fisheries Science Center's (SEFSC) Miami Laboratory. Two hundred ninety-eight records were

acquired from four data bases maintained at the

NMFS SEFSC Galveston Laboratory, including 260

tag return records of head-started turtles and 38

records of either wild Kemp's ridleys caught incidentally to fishing, rehabilitated turtles, or sightings of

sea turtles. Four records were acquired from the sea

turtle data base at the NMFS Laboratory in

Pascagoula, Mississippi, and 57 records, including 13

records of nesting Kemp's ridleys, were acquired

from the published literature (Werler 1951; Carr

1%1; Hildebrand 1963; Chavez 1967; Molinar 1973;

Francis 1978; Fuller 1978; Hildebrand 1980; Rabalais

and Rabalais 1980; Fritts and Reynolds 1981; Shaver

et al. 1988; Ogren 1989). Only those records positively identifying Kemp's ridleys were used and each

record was verified to avoid duplication.

The coast of Texas was divided into 8 regions. Regions were selected for clarity in plotting; however,

boundaries of major bay systems were also considered

(Fig. 1). From northeast to southwest, the regions

consist of the following: region I-Sabine Pass/High

Island Area; region 2-Bolivar Peninsula/Galveston

Area; region 3-Freeport/East Matagorda Bay; region 4-Matagorda Bay and Peninsula; region

5-San An tonio Bay/Copano Bay/Matagorda Island;

region 6-Corpus Christi Bay/Northern Padre Island; region 7-Central Laguna Madre/Padre Island;

region 8-Southern Laguna Madre/Padre Island.

Most data fall within the regional boundaries; those

occurring outside are shown on maps of the entire

Texas coastline and are labeled region 9 on the tables

and graphs.

Four categories of Kemp's ridleys are used

throughout the atlas. Because there was no data base

available for sea turtle records before 1980, two categories of wild turtles are presented. Wild turtles

recorded prior to 1980 are classifed as historical

records and represented by a circle. The majority of

historical records are from the literature. Wild turtles

recorded from 1980 to the present are represen ted

by a triangle and the majority of these records were

gathered from the STSSN data base. Head-started

turtles (turtles reared, tagged, and released as part of

the head-start conservation project) are represented

by a square. Nesting turtles, identified separately because Texas is the northern extreme of the nesting

range, are represented by a diamond.

The plotted symbols represent approximate turtle

locations. Latitude and longitude were usually estimated in reports of turtle strandings, tag returns,
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 3

sightings, and incidental catches. Each symbol may

represent more than one turtle. In some instances,

numerous turtles were commonly found in the same

area and were assigned the same latitude and longitude. The number of turtles that occur in each

region are found in the map legends.

Results _

Geographic Distribution

The authors warn the readers that the distribution

data comparing numbers of turtles between regions

may be biased owing to the fact that the eight regions

are not comparable in size or coastal area. However,

we believe that, because the regions are based on the

boundaries of major bay systems, the information is

useful presented in this manner. Information on the

distribution of head-started and wild Kemp's ridleys

within select bay systems is frequently requested by

sea turtle biologists.

Most Kemp's ridleys were reported from regions

,1,2, 5, and 6, the northeast and central areas of the

coastline (Fig. 2). The frequency of head-started,

wild, historical, and nesting Kemp's ridleys is summarized by region in Figure 3. Head-started ridleys were

most numerous in regions 2, 5, and 6 (Figs. 5, 8, and

9). Wild Kemp's ridleys were found most frequently

in regions 1, 2, and 6 (Figs. 4, 5, and 9). Historical

records show wild Kemp's ridleys occurred most frequently in regions 6 and 8 (Figs. 9 and 11), and

reports of nestings were concentrated along the

central to south Texas coast in regions 6, 7, and 8

(Figs. 9, 10, and 11). Head-started Kemp's ridleys

were more frequently reported farther offshore, outside the regional boundaries, than wild Kemp's

ridleys (Fig. 12).

Kemp's ridleys were found both offshore (any

beach or body of water seaward of barrier islands)

and inshore (any beach or body of water landward of

barrier islands) with the exception of inshore waters

of region 7 (Fig. 10), which includes the central Laguna Madre. Only two historical records documented

Kemp's ridleys from the inshore waters of region 8

(Fig. 11), farther south in the Laguna Madre.

A summary by region and recovery method, of

head-started, wild, and historical Kemp's ridleys is

presented in Table 1. Six hundred and forty (74.0%)

of the 865 turtles were found stranded on the beach

(dead or alive). One hundred and thirty-nine (16.0

%) were caught incidentally to commercial or recreational fishing and 73 (8.4%) were reported either in

power plant intakes, as turtle sightings, captured at

the water's surface, or were reported without recovery method. The 13 (1.5%) records of nesting turtles

are not summarized in Table 1. Head-started turtles

were reported more frequently than wild Kemp's

ridley's in shrimp trawls.

Seasonal Distribution

Eight hundred and fifty records were used for the

seasonal distribution data. Dates for 15 of the 865

records were unknown. Seasons were defined as the

following: winter Qanuary, February, March), spring

(April, May, June), summer Quly, August, September), and fall (October, November, December). Six

hundred and forty-four (75.7%) Kemp's ridleys were

reported during the spring and summer (Fig. 13).

Seasonal data may be biased, however, owing to an

increase in recreational activities along the coast during spring and summer, which may increase the

chances of a stranded turtle being found. An increase

in recreational and commercial fishing also occurs at

this time, and Kemp's ridleys are caught incidentally

to these fisheries. Head-started turtles (n=259) were

reported most frequently in the spring (52.9%) and

summer (31.3%), followed by winter (8.5%) and fall

(7.3%) (Fig. 14). Wild Kemp's ridleys (n=544) were

reported most frequently in spring (40.3%) and summer (31.2%), followed by fall (18.6%) and winter

(9.9%). One turtle nested in winter (late March)

while all others (12) nested in spring. Seasonal distribution maps are presented in Figures 15-23.

Most strandings and shrimp trawl catches were reported in spring, whereas most turtles caught by

hook and line were reported in summer (Table 2.).

Both head-started and wild turtle records followed

this pattern.

Size Distribution _

Of the 865 Kemp's ridley records, 546 contained

measurements. Curved carapace lengths (CCL) were

recorded more frequently than straight carapace

lengths (SCL); therefore SCL measurements were

converted to CCL for size classification. The conversion formula, based on the regression of 144 pairs of

SCL and CCL measurements is CCL = 1.06 X SCL (r

=0.99, P=O.OOOI). Three size classes, based on

Ogren's (1989) classifications, were used in the data

summary: < 20 cm Uuveniles), 20-59.9 cm (subadults), and 60 cm (adults). Four hundred and

twelve (75.4%) of the turtles were 20-59.9 cm CCL,
4 NOAA Technical Report NMFS 110

Table 1

Frequency of Kemp's ridleys" by region and recovery method. Percentages are based on 865 turtlesb•

Stranded Shrimp trawl Other bycatch C Otherd

# % # % # % # %

Region 1

Head-started II 1.3 8 0.9 7 0.8 6 0.7

Wild 165 19.1 4 0.5 II 1.3 4 0.5

Historical 0 0.0 0 0.0 I 0.1 0 0.0

Total 176 20.4 12 1.4 19 2.2 10 1.2

Region 2

Head-started 14 1.6 13 1.5 2 0.2 7 0.8

Wild III 12.8 4 0.5 6 0.7 4 0.5

Historical 0 0.0 0 0.0 2 0.2 I 0.1

Total 125 14.4 17 2.0 10 1.1 12 1.4

Region 3

Head-started 6 0.7 II 1.3 2 0.2 2 0.2

Wild 14 1.6 0 0.0 2 0.2 0 0.0

Historical 0 0.0 0 0.0 1 1.0 2 0.2

Total 20 2.3 11 1.3 5 0.5 4 0.4

Region 4

Head-start 5 0.6 12 1.4 3 0.3 5 0.6

Wild 27 3.1 I 0.1 0 0.0 0 0.0

Historical 0 0.0 0 0.0 0 0.0 0 0.0

Total 32 3.7 13 1.5 3 0.3 5 0.6

Region 5

Head-started 70 8.1 13 1.5 5 0.6 7 0.8

Wild 18 2.1 3 0.3 1 0.1 2 0.2

Historical 0 0.0 2 0.2 0 0.0 1 0.1

Total 88 10.2 18 2.0 6 0.7 10 1.1

Region 6

Head-started 22 2.5 3 0.3 I 0.1 12 1.4

Wild 104 12.0 2 0.2 3 0.3 2 0.2

Historical 16 1.9 I 0.1 0 0.0 0 0.0

Total 142 16.4 6 0.6 4 0.4 14 1.6

Region 7

Head-started 0 0.0 0 0.0 I 0.1 0 0.0

Wild 33 3.8 0 0.0 2 0.2 2 0.2

Historical 1 0.1 0 0.0 0 0.0 0 0.0

Total 34 3.9 0 0.0 3 0.3 2 0.2

Region 8

Head-started 1 0.1 0 0.0 0 0.0 0 0.0

Wild 13 1.5 0 0.0 I 0.1 2 0.2

Historical 6 0.7 0 0.0 3 0.3 8 0.9

Total 20 2.3 0 0.0 4 0.4 10 1.1

Region 9

Head-started 2 0.2 7 0.8 0 0.0 2 0.2

Wild 1 0.1 1 0.1 0 0.0 3 0.3

Historical 0 0.0 0 0.0 0 0.0 1 0.1

Total 3 0.3 8 0.9 0 0.0 6 0.7

Subtotal

Head-started 131 15.1 67 7.8 21 2.4 41 4.7

Wild 486 56.2 15 1.7 26 3.0 19 2.2

Historical 23 2.7 3 0.3 7 0.8 13 1.5

Total 640 74.0 85 9.8 54 6.2 73 8.4

" Thirteen nesting turtles, not listed in this table, totaled 1.5% of the 865 turtles. b Due to rounding errors, percentages may not add up [Q 100%. C "Other bycatch" includes: turtles caught by hook and line and by gill net. d "Other" includes turtles dip-netted or caught by hand while swimming at the surface, tu.rtles found in power plant intakes, sightings

of turtles. and turtles with no recovery method.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 5

Table 2

Frequency of Kemp's ridleys· by season and recovery method. Percentages are based on 850 turtlesb

•

Stranded Shrimp trawl Other bycatch C Otherd

# % # % # % # %

Winter

Head-started 14 1.6 6 0.7 0 0.0 2 0.2

Wild 52 6.1 2 0.2 0 0.0 0 0.0

Historical 3 0.3 I 0.1 0 0.0 I 0.1

Total 69 8.0 9 1.0 0 0.0 3 0.3

Spring

Head-started 83 9.8 27 3.2 8 0.9 19 2.2

Wild 199 23.4 6 0.7 5 0.6 9 1.0

Historical I 0.1 2 0.2 0 0.0 0 0.0

Total 283 33.3 35 4.1 13 1.5 28 3.2

Summer

Head-started 27 3.2 25 2.9 13 1.5 16 1.8

Wild 139 16.3 6 0.7 17 2.0 8 0.9

Historical 8 0.9 0 0.0 3 0.3 II 1.3

Total 174 20.4 31 3.6 33 3.8 35 4.0

Fall

Head-started 7 0.8 9 1.0 0 0.0 3 0.3

Wild 96 11.3 I 0.1 2 0.2 2 0.2

Historical I 0.1 0 0.0 2 0.2 I 0.1

Total 104 12.2 10 1.1 4 0.4 6 0.6

• Thirteen nesting turtles totaled 1.5% of the 850 turtles.

b Owing to rounding errors, percentages may not add up to 100%.

C "Other bycatch" includes turtles caught by hook and line and by gill net.

d "Other" includes turtles dip-netted or caught by hand while swimming at the surface, turtles found in power plant intakes, sightings

of turtles, and turtles with no recovery method.

101 (18.5%) 60 cm, and only 33 (6.1 %) < 20 cm

(Fig. 24). Wild Kemp's ridleys (n=486) were reported

most frequently in the 20-59.9 cm (73.0%) ) range,

followed by 60 cm (21.6%) and < 20 cm (5.3%)

(Fig. 25). Head-started turtles (n=54) were reported

most frequently in the 20-59.9 cm (98.2%), of which

20.3% were 40 cm eeL. Only 1.8% of head-started

turtles were < 20 cm and no head-started turtles were

reported 60 cm. Measurements for nesting turtles

were not available. Size distribution maps are presented in Figures 26-34. A summary of head-started,

wild, and historical Kemp's ridleys, by size and recovery method, is presented in Table 3.

Discussion _

Kemp's ridley sea turtles were found along the entire

Texas coast, but most frequently in the northeastern

and central regions. The infrequent occurrence of

Kemp's ridleys in the inshore habitat of the two

southernmost regions of the coast may be attributed

to the type of habitat found in the Laguna Madre.

This hypersaline area differs from all other Texas estuaries in having clear, shallow waters and a hard

sand bottom (Diener 1975). Little or no commercial

crab and shrimp fishing exist in this inshore area

(Margot Hightower, SEFSe, NMFS, Galveston, TX

77551, pers. commun. May 1991). Large beds of seagrasses and algae are present and green sea turtles

(Chelonia mydas), which feed on the grasses and algae, are found in the southern reaches of the Laguna

Madre. The northern and central Texas estuaries are

bordered by tidal marshes and mud flats and have

more turbid waters (Diener 1975). They support

commercial fisheries for crab and shrimp (Margot

Hightower, SEFSe, NMFS, Galveston, TX 77551, pers

comm. May 1991).

Fishes, crabs, and the gastropod scavenger

Nassarius were the most frequently identified food

items in the stomachs of 49 Kemp's ridleys that were

found stranded along the northern Texas coast between 1986 and 1989 (Stanley, in prep.). Similar

results were reported by Owens (1986) based on the

examination of stomachs from 77 Kemp's ridleys (including 47 head-started turtles) stranded along the

central Texas coast. Owens suggested that turtles feed

on trawler bycatch, because of the presence of fish
6 NOAA Technical Report NMFS 110

Table 3

Frequency of Kemp's ridleysa by size and recovery method. Percentages are based on 546 turtles b

.

Stranded Shrimp trawl Other bycatch C Otherd

# % # % # % # %

<20 em

Head-started 1 0.2 0 0.0 0 0.0 0 0.0

Wild 24 4.4 2 0.4 0 0.0 0 0.0

Historical 1 0.2 0 0.0 3 0.6 0 0.0

Total 26 4.8 2 0.4 3 0.6 0 0.0

20-59.9 em

Head-started 38 7.0 7 1.3 7 1.3 1 0.2

Wild 325 59.5 7 5.7 21 3.9 2 0.4

Historical 0 0.0 0 0.0 2 0.4 0 0.0

Total 363 66.5 14 2.5 30 5.7 3 0.6

~60 em

Head-started 0 0.0 0 0.0 0 0.0 0 0.0

Wild 104 19.0 1 0.2 0 0.0 0 0.0

Historical 0 0.0 0 0.0 0 0.0 0 0.0

Total 104 19.0 I 0.2 0 0.0 0 0.0

a No measurements were recorded for the thirteen nesting turtles.

b Owing to rounding errors, percentages may not add up to 100%. C "Other bycatch" includes turtles caught by hook and line and by gill net.

d "Other" includes turtles dip-netted or caught by hand while swimming at the surface, turtles found in power plant intakes, sightings

of turtles, and turtles with no recovery method.

(which turtles could not normally catch) and the gastropod scavenger Nassanus (an indicator that the

food was dead when it was eaten) in the gut contents

of stranded turtles. The fishes and crabs favored by

the Kemp's ridleys are more plentiful in the northeastern and central estuaries of Texas. Therefore,

these areas seem to be a more suitable habitat than

the southern areas.

Head-started and wild Kemp's ridleys were found

in the same areas. Both head-started and wild

Kemp's ridleys were most numerous in regions 2

and 6, the Bolivar/Galveston area and the Corpus

Christi/North Padre Island area. Region 6 was the

primary release area (Fig. 1) for most head-started

Kemp's ridleys (Fontaine et al. 1990). A high number of head-started turtles were reported from

region 5 which includes Copano Bay, a head-start

release site in 1985 (Manzella et al. 1988). Wild

Kemp's ridleys were also numerous in region 1, the

Sabine Pass/High Island area. Region 1 was the

fourth most numerous region for head-started

turtles. This area is considered a major feeding

ground for Kemp's ridleys (Ogren 1989). Only two

head-started Kemp's ridleys were reported from regions 7 and 8, the southern areas of the coast. Wild

Kemp's ridleys were also infrequently reported from

these regions.

Head-started turtles were more frequently reported

farther offshore and in shrimp trawls than wild

Kemp's ridleys. This may be due to the fact that headstarted turtles bear a tag, which may prompt the

public to report the turtles more readily than untagged

turtles.

Both head-started and wild Kemp's ridleys were

more frequently reported in the spring and summer.

Head-started and wild Kemp's ridleys occurred

more frequently in the 20-59.9 cm CCL size class and

could be considered sub-adults (Ogren 1989). The

average size of head-started turtles at release was

16-18 cm SCL. Most tag returns of head-started

turtles, reported with measurements, occurred in the

20-59.9 cm eCL range (n=53) and 21 % were> 40

cm. These measurements suggest these turtles do

adapt and grow, after release into their natural habitat. Apparently the most common size class of ridleys

found in the Gulf of Mexico is 20-59.9 cm. (Ogren

1989; Schmid and Ogren 1990).

The present atlas illustrates the distribution of

head-started and wild Kemp's ridleys along the Texas

coast. The head-started turtles do seem to adapt to

the wild and are found in the same areas as wild

Kemp's ridleys. Tag returns of head-started turtles

found in other areas of the Gulf of Mexico and the

Atlantic coast of the United States (n=425), also sug-
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 7

gest that these turtles adapt to the wild after release

and are found in the same areas as wild Kemp's ridleys (Manzella et al. 1988; Fontaine et a1.1989a).

Similar atlases showing the distribution of known

records of Kemp's ridleys throughout their entire

range would be useful to sea turtle biologists, conservationists, and agencies responsible for protection

and management of this endangered species.

Acknowledgments

We would like to thank the following Texas Atlas contributors: Wendy Teas, STSSN, NMFS Miami

Laboratory; Marcel Duronslet and Dickie Revera,

NMFS Galveston Laboratory; Rick Minkler, NMFS

Pascagoula Laboratory; and all STSSN participants.

Special thanks go to Larry Ogren, Terry Henwood,

Charles Caillouet Jr., and others who reviewed the

manuscript and made helpful suggestions during

preparation of the atlas. Also, we thank Glen

Machlan of the NOAA Library in Rockville, Maryland, for helping with the literature search.

Citations

Bleakney, S.

1965. Reports of marine turtles from New England and eastern Canada. The Canadian Field Naturalist 79:120-128.

Brongersma, L. D.

1972. European Atlantic turtles. Zoologische Verhandelingen

121:318 p., 12 pit., 8 maps.

Brongersma, L. D., and A. F. Carr

1983. Lepidochelys kempi (Garman) from Malta. Proceedings

of the Koninklijke Nederlandse Akademie, Serie C,

86(4) :445-454.

Carr, A.

1955. The riddle of the ridley. Animal Kingdom 58(5):

146-156.

1957. Notes on the zoogeography of the Atlantic sea turtles

of the genus Lepidochelys. Revista De Biologica Tropical

5(1):45-61.

1961. The ridley mystery today. Animal Kingdom 64(1):7-12.

Carr, A., and D. K. Caldwell

1958. The problem of the Atlantic ridley turtle (Lepidochelys

kempi) in 1958. Revista Biologica Tropical 6(2):245-262.

Chavez, H. M.

1967. Nota preliminar sobre la recaptura de ejemplares

marcados de tortuga lora, Lepidochelys olivacea kempii. Boletin

del Programa Nacional de Marcado de Tortugas Marinas

1(6): 373-377.

Chavez, H. M., M. Contreras G., and T P. E. Hernandez D.

1968. On the coast of Tamaulipas (Part One). International

Turtle & Tortoise Society Journal 2(4):20-29, 37.

1968. On the coast of Tamaulipas (Part Two). International

Turtle & Tortoise SocietyJournal 2(5):16-19, 27-34.

Diener, R. A.

1975. Cooperative Gulf of Mexico estuarine inven tory and

study-Texas: area description. NOAA Technical Report

NMFS CIRC - 393, 129 p.

Duronslet, M.j., D. B. Revera, and K. M. Stanley.

1991. Marine debris and sea turtle strandings on beaches of

the upper Texas and southwestern Louisiania coasts, June

1987 through September 1989. NOAA Technical Memorandum NMF5-SEFC-279, 47 p.

Fletcher, M. R.

1989. The National Park Service's role in the introduction of

Kemp's ridley sea turtle. In Proceedings of the first international symposium on Kemp's ridley sea turtle biology,

conservation and management (C. W. CaillouetJr. and A. M.

Landry Jr., eds.), p. 7-9. Texas A&M University, Sea Grant

College Program, TAMU-SG-89- 105.

Fontaine, C. T., S. A. Manzella, T D. Williams, R. M. Harris, and W.

j. Browning.

1989a. Distribution, growth and survival of head started,

tagged and released Kemp's ridley sea turtles (Lepidochelys

kemp,) from year-classes 1978-1983. In Proceedings of the

first international symposium on Kemp's ridley sea turtle

biology, conservation and management (C. W. Caillouet Jr.

and A. M. Landry Jr., eds.), p. 124-144. Texas A&M University, Sea Grant College Program, TAMU-SG-89-105.

Fontaine, C. T, T. D. Williams, S. A. Manzella, and C. W. Caillouet

Jr.

1989b. Kemp's ridley sea turtle head start operations of the

NMFS SEFC Galveston Laboratory. In Proceedings of the

first international symposium on Kemp's ridley sea turtle

biology, conservation and management (C. W. Caillouet Jr.

and A. M. Landry Jr., eds.), p. 96-110. Texas A&M University, Sea Grant College Program, TAMU-SG-89-105.

Fontaine, C. T., M. j. Duronslet, D. B. Revera, T D. Williams, j.

A.Williams, S. A. Manzella, E. K. Stabenau, A. M. Landry Jr., and

C. W. CaillouetJr.

1990. Kemp's ridley head start experiment and other sea

turtle research at the Galveston Laboratory: annual report -

fiscal year 1989. NOAA Technical Memorandum NMF5-

SEFC-266, iv plus 28 p.

Francis, K.

1978. Kemp's ridley sea turtle conservation programs at

South Padre Island, Texas and Rancho Nuevo, Tamaulipas,

Mexico. Florida Marine Research Publications 33:51-52.

Fritts, T. H., and R. P. Reynolds.

1981. Pilot study of the marine mammals, birds and turtles

in OCS areas of the Gulf of Mexico. U. S. Fish and Wildlife

Service, Office of Biological Services, Washington, D. C.

FWS/OBS-81/36, 139 p.

Fuller, D. A.

1978. The habitats, distribution, and incidental capture of

sea turtles in the Gulf of Mexico. Louisiana State University, Baton Rouge, LA, LSU-CFI-85-31, 44 p.

Heinly, R. W., E. K. Stabenau, A. M. Landry Jr., and M. Duronslet.

1988. Mutilation of stranded sea turtles along the Texas

coast, p. 33-34. In Proceedings of the eighth annual workshop on sea turtle conservation and biology (B. A. Schroeder,

compiler). NOAA Technical Memorandum NMF5-SEFC-214,

iii plus 135 p.

Hildebrand, H. H.

1963. Hallazgo del area de anidacion de la tortuga marina

"lora", Lepidochelys kempi (Garman), en la costa occidental

del Golfo de Mexico. Sobretiro de Ciencia 22(4):105-112.

1980. Kemp's ridley or tortuga lora, Lepidochelys kempi

(Garman). Unpublished report to Southeast Fisheries

Center, NMFS, 6 p.

Manzella, S. A., C. W. CaillouetJr., and C. T Fontaine.

1988. Kemp's ridley, Lepidochelys kempi, sea turtle head start

tag recoveries: distribution, habitat, and method of

recovery. Marine Fisheries Review 50(3):24-32.
8 NOAA Technical Report NMFS 110

Meylan, A., P. Castaneda, C. Coogan, T Lozon, and]. Fletemeyer.

1990. First recorded nesting by Kemp's ridley in Florida,

USA. Marine Turtle ewsletter 48:8-9.

Molinar, T P. E. Vargas.

1973. Resultados preliminares del marcado de tortugas marinas en aguas Mexicanas (1966-1977). Instituto Nacional

de Pesca/Serie Informativa (INP/SI): i12, 27 p.

Ogren, L. H.

1989. Distribution of juvenile and sub-adult Kemp's ridley

turtles: preliminary results from the 1984-1987 surveys. In

Proceedings of the first international symposium on Kemp's

ridley sea turtle biology, conservation and management (C.

W. Caillouet Jr. and A. M. Landry Jr., eds.), p. 116-123.

Texas A&M University, Sea Grant College Program, TAMUSG-89-105, vi plus 260 p.

Owens, D.

1986. Recent L. kempi necropsy results from Texas.

Unpublished report to Kemp's ridley recovery team, 4 August 1986, 40 p.

Pritchard, P. C. H., and R. Marquez M.

1973. Kemp's ridley turtle or Atlantic ridley. International

Union for Conservation of Nature and Natural Resources

(IUCN) Monograph No.2: Marine Turtle Series, 30 p.

Rabalais, S.C., and N. N. Rabalais.

1980. The occurrence of sea turtles on the south Texas

coast. Contributions in Marine Science 23:123-129.

Schmid,]. R., and L. H. Ogren.

1990. Results of a tagging study at Cedar Key, Florida, with

comments on Kemp's ridley distribution in the southeastern

U. S. In Proceedings of the tenth annual workshop on sea

turtle biology and conservation (T H. Richardson, ]. 1.

Richardson, and M. Donnely, compilers), p. 129-130. NOAA

Technical Memorandum NMFS-SEFC-278.

Shaver, D.]., E. Cheeseman, and]. Bjork.

1988. National Parks Service, Padre Island National Seashore. Action plan for nesting sea turtles, nests and hatchlings on Texas beaches from Matagorda Island

southward. Unpublished report, 39 p.

Stanley, K.

In prep. Feeding ecology of the Loggerhead (Caretta caretta)

and Kemp's ridley (Lepidochelys kempi) sea turtles in the

Northwestern Gulf of Mexico. M.S. thesis, Texas A&M

University at Galveston. Galveston, Texas.

Werler,]. E.

1951. Miscellaneous notes on the eggs and young of Texan

and Mexican reptiles. Zoologica 36(3).

Wibbels, T, N. Frazer, M. Grassman, ]. Hendrickson, and P.

Pritchard.

1989. Blue ribbon panel review of the National Marine Fisheries Service Kemp's ridley headstart program. Report

submitted to the Southeast Regional Office, National Marine Fisheries Service, August 1989, i plus 11 p.
Figure 1

The Texas coast divided into eight regions.

The offshore area, outside the regional

boundaries, is region 9. Major release sites

of headstarted turtles are also shown.

Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 9

Texas

2

3

4

Region 1 - Sabine Pass/High Island Area

Region 2 - Bolivar Peninsula/Galnston Aru

r"E-......,H'-I-"'T"-.... Region 3 - Freeport/East Matagorda Bay

Region 4 - Matagorda Bay and Peninsula

Region :5 - San Antonio Bay /Copano Bay /Matagorda Islan d

Region 6 - Corpus Christi Bay /NortheFn Padre Island

Region 7 - Central Laguna Madre/Padre Island

Region 8 - Southern Laguna Madre/Padre Island

Region 9 - Offshore aru, outsidf' regionaI boundries

• - Major hf'ad-start rf'luse sites

t

N

25

20

15

10

5

o

Figure 2

Frequency distribution of Kemp's

ridleys found along the Texas coast.

7 6 5

Region

4 3 2
10 NOAA Technical Report NMFS 110

n=865

Figure 3

Frequency distribution of Kemp's ridley groups, by

region.

25

25

20

20

15

C 15 CIl

10 CIl

a.. 10

5

5

0

0

Head-started - 0 (32)

Wild - 6 (184)

Historical - 0 (1)

o

Gulf

of 6

Mexico

t

N

Figure 4

Geographic distribution of Kemp's ridleys In

region 1 - Sabine Pass/High Island area.
Figure 5

Geographic distribution of Kemp's

ridleys in region 2 -

Bolivar Peninsula/

Galveston area.

Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 11

Head-storted - D (36)

WHd - A (125)

Historical - 0 (3)

D

Gulf

of

Mexico

t

N

Head-started - 0 (21)

Wild - 6 (16)

Hjstorjcal - 0 (3)

o DO

Gulf

of

Mexjco

o

Figure 6

Geographic distribution of

Kemp's ridleys in region 3 -

Freeport/East Matagorda

Bay.

o

o

t

N
12 NOAA Technical Report NMFS 110

Gulf

of

Mexico

Head-started - D (25)

Wild 6 (28) t

N

Figure 7

Geographic distribution of Kemp's

ridleys in region 4 - Matagorda Bay

and Peninsula.

Head-started -

Wild

Hlstorlcal

[J (95)

6. (24)

0(3)

Gulf

of

Mexlco t

N

Figure 8

Geographic distribution of Kemp's

ridleys in region 5 - San Antonio Bayl

Copano BayIMatagorda Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 13

Figure 9

Geographic distribution of Kemp's ridleys

in region 6 - Corpus

Christi Bay/Northern

Padre Island.

6ulf

of

Mexico

[J

Head-started - [J (38)

WlId - l!t. (111)

Histoncal - 0 (17)

Nesters - ¢ (7)

t

N

27"50' N

Figure 10

Geographic distribution of Kemp's

ridleys in region 7 - Central Laguna

Madre/Padre Island.

Head-started - D (I)

Wild -6 (37)

Historical -0 (I)

Nesters -0 (3)

Gulf

of

Mexico

. Padre

: Island

::.

t

N
Figure 12

Geographic distribution of Kemp's ridleys outside the regional boundaries. The

wild turtle positioned on land near region 2 was found in a drainage ditch in

Houston, TX.

Figure 11

Geographic distribution of Kemp's ridleys in

region 8 - Southern Laguna Madre/Padre Island.

N

t

o

t

N

2

o

DO

o

South

Padre

6. Island

Gulf

of

Mexico

Gulf

of

Mexico

o

Head-started - 0 (11)

Wild - 6. (5)

Historical - 0 (1)

4

o

o

o

Head-started - 0

~jld - A

Historical

Nesters

Texas

14 NOAA Technical Report NMFS 110

97°10' IN
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 15

Figure 13

Frequency distribution of Kemp's ridleys, by

season.

n=850

45

40

35

30

"E 25

e

8!. 20

15

10

5

0

Winter Spring

n=850

Summer Fall

Figure 14

Frequency distribution of Kemp's ridley groups,

by season.

30

25

20

15

10

5

o

30

25

20

15

10

5

o

Wild

Head-started

Historical

Nesters
16 NOAA Technical Report NMFS 110

Head-started - [J (2)

Wild - a (6)

Gulf

of

Mexico

Winter

Head-stDrted - [] (6)

Wild - a (63)

Gulf

of

Mexico

Spring

t

N

t

N

Figure 15

Seasonal distribution of Kemp's ridleys in region 1 - Sabine

Pass/High Island area.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 17

Heed-started

Wild

[] (20)

A (04)

[]

[] A

Figure 15 (continued)

Gulf

of

Mexico

Summer

Heed-sterted - [] (3)

W1Jd - A (30)

Histort cel - 0 (1)

Gulf

of

Mexico

Fell

A

t

N

t

N
18 NOAA Technical Report NMFS 110

W1nter

Spring

Head-started - [] (2)

Wlld - A (10)

Gulf

of

Mex1co

t

N

Head-started - [] (25)

Wl1d - A (61)

Gulf

of

Mexico

t

N

29~O' N

29~O' N

Figure 16

Seasonal distribution of Kemp's ridleys in region 2 - Bolivar Peninsula/

Galveston area.
Figure 16 (continued)

Summer

Fall

Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 19

Head-started - C (4)

Wild - Ii. (27)

Historical - 0 (3)

2'''30' N

o

Gulf

of

Mexico

2"10'

t

N

Head-started - C (5)

Wild -Ii. (26)

c

Gulf

of

Mexico

Ii.

t

N
20 NOAA Technical Report NMFS 110

"-40'

Head-started - C (2)

Wild - t:. (2)

[]

Winter

W40'

Head-started - C (14)

Wild t:. (5)

Spring

W30'.."

Gulf

of

Mexico

6ulf

of

Mexico

t

N

t

N

Woo'N

Figure 17

Seasonal distribution of Kemp's ridleys in region 3 - Freeport/East

Matagorda Bay.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 21

o

Summer

Hoad-sterted

Wild

Historical

[J (4)

- (5)

0(2)

o

Gulf

of

Mexico

t

N

Figure 17 (continued)

Head-started - a (1)

Wild - 6. (4)

Hjstor1cal - 0 (1)

Fell

Gulf

of

Mexico

t

N
22 NOAA Technical Report NMFS 110

Gulf

of

Mexico

IWild - A (2)1

Winter

/

...: ..

.. ":" . .::'.

Gulf

of

Mexico

Head-started - D (12)

Wild - A (11)

Spring

t

N

t

N

28~0' N

28"20'

Figure 18

Seasonal distribution of Kemp's ridleys in

region 4 - Matagorda Bay and Peninsula.
Summer

Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 23

96°10''w'

Gulf

of

Mexico 28°20'

Head-started - [] ( 13) t

Wild - t:. (5)

N

Figure 18 (continued)

Fell

Metllgofde

Bey

/ " .-t 0: "

.... :.:. . ::.... 6

..

IWild - A <to>1

Gulf

of

Mexico

t

N
24 NOAA Technical Report NMFS 110

Head-started - lJ (6)

Wild - 6 (1)

Historical -0 (I)

Winter

Gulf

of

Mexico t

N

Head-started

Wild

Histonea1

Spring

lJ (62)

6 (15)

o (2)

Gulf

of

Mexico t

N

Figure 19

Seasonal distribution of Kemp's ridleys in

region 5 - San Antonio Bay/Copano Bay/

Matagorda Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 25

Summer

He!td-storted

Wild

0(20)

- A (4)

Gulf

of

MeXICO t

N

Figure 19 (continued)

Heod-storted - 0 (7)

Wild - A (4)

Fall

Gulf

of

Mex1co t

N
26 NOAA Technical Report NMFS 110

Winter

Head-started

WIJd

Historical

GUlf

of

Mexico

- C (8)

- 6 (22)

-0(1)

t

N

27~'

Gulf

of

Mexico

Spring

Head-started

Wild

Nesters

-0

-6

-<>

(16)

(44)

(7)

t

N

2-roSO' N

Figure 20

Seasonal distribution

of Kemp's ridleys in

region 6 - Corpus

Christi Bay/Northern Padre Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 27

Summer

Head-started

Wlld

Historical

Gulf

of

Mexico

[]

[J (13)

(j, (32)

0(7)

t

N

Gulf

of

Mexico

Figure 20 (continued)

Fall

Head-started - [] (I)

Wild -l!. (13) t

N
28 NOAA Technical Report NMFS 110

WHd -A(l1)

Nesters - <> (1)

Winter

Head-started - D

Wild - 6.

Nesters 0

Spnng

:. Padre

:; Island

Padre

Island

Gulf

of

Mexico

1"000'

t

N

Gulf

of

Mexico

t

N

Figure 21

Seasonal distribution of Kemp's ridleys in region

7· Central Laguna Madre/Padre Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 29

GUlf

of

Mexico

a ..

t

N

Summer

Figure 21 (continued)

Wild

Hlstoricnl

Fall

6 (7)

0(1)

:Pedn

.:.1s1end

Gulf

of

Mexico

t

N
30 NOAA Technical Report NMFS 110

..•.

6ulf

of

Mextco

South

oPedre

Island

t

N

Winter

Wild

Htstorical

Nesters

Sprtng

GUlf

of

Mextco

South

Padre

Island

t

N

26"30'N

Figure 22

Seasonal distribution of Kemp's ridleys in region 8 -

Southern Laguna Madre/Padre Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 31

97~' 97·'O'W

Heed-stnted - D (1)

Wild - 6 (5)

H1stor1cel - 0 ( 10)

Summer

Gulf

of 26·30'N

Mexico

South

Padre

6 Island

t

N

Figure 22 (continued)

Fall

Gulf

of

Mexico

.6South

6PDdre

61s1Dnd
32 NOAA Technical Report NMFS 110

Texas

2

o

3

4

Gulf

of

Mexico

IHeDd stDrted - 0 (2) I

t

N

Winter

Texas

2

3

4

Gulf

of

Mexico

Head started - 0 (1)

Wild - 6 (2)

o

1

t

N

Figure 23

Seasonal distribution of Kemp's ridleys outside

the regional boundaries. The wild turtle positioned on land near region 2 on the Fall map,

was found in a drainage ditch in Houston, TX.

Spring
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 33

t

N

[J

o

2

o

o

3

Gulf

of

Mexico

4

Hsnd stnrted - 0 (6)

Wild - t:. (I)

[J

Texos

Summer

Figure 23 (continued)

Texas

2

3

4

o

Gulf

of

Mexico

Head storted - 0 (2)

Wild - t:. (2)

Historical - 0 (1)

t

N

Fnll
34 NOAA Technical Report NMFS 110

n=546

80

70

60

50 ...

c:

40 Q)

a..

30

20

10

0

<20cm 2Q-59.9cm ~60cm

Figure 24

Curved carapace length measurements of

Kemp's ridleys found along the Texas coast.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 35

n=546

Figure 25

Frequency distribution of Kemp's ridley groups,

by curv.ed carapace lengths.

70

60

50

40

30

20

10

o

70

60

50

40

30

20

10

o

Wild

Head-started

Historical

Nesters
36 NOAA Technical Report NMFS 110

IHistorical - 0 (1) I

::.~~~.~:(:...

.::., ::

o

Gulf

of

Mexico

< 20 cm

Heod-storted - [J (6)

Wild - Ii (157)

Gulf

of

Mexico

20 - 59.9 em

t

N

t

N

Figure 26

Size distribution of Kemp's ridleys in region 1 - Sabine

Pass/High Island area.
Figure 26 (continued)

Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 37

Gulf

of

Mexico

t

N

!60 cm
38 NOAA Technical Report NMFS 110

< 20 cm

o

Wl1d

Historical

Gulf

of

Mexl co

I:> (3)

0(1)

t

N

20 - 59.9 em

Gulf

of

Mexico

t

N

Figure 27

Size distribution of Kemp's ridleys in

region 2 - Bolivar Peninsula/Galveston

area.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 39

Figure 27 (continued)

2.60 em

~OO'

IWild - /j, (22)1

Gulf

of

Mex1co

t

N
40 NOAA Technical Report NMFS 110

'Historical - 0 (nl

< 20 cm

Head-started - C (3)

Wild - Ii. (5)

20 - 59.9 cm

9:Mo''W

95"30' 'W

Gulf

of

Mexico

Gulf

of

Mexico

t

N

t

N

2~'N

Figure 28

Size distribution of Kemp's ridleys in

region 3 - Freeport/East Matagorda

Bay.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 41

95"40'

IWftd - A (6) I

~':'''''"'':~'' ....A .....

Gulf

of

MexIco

Figure 28 (continued)

!60 em

t

N
42 NOAA Technical Report NMFS 110

Matllgorda

Day

.::"~.:.:::.:..

:: .::.: .

Gulf

of

Mextco

< 20 em

t

N

20 - 59.9 em

Head-stllrted

Wtld

c (3)

- 11 (13) t

N

Figure 29

Size distribution of Kemp's ridleys

in region 4 - Matagorda Bay and

Peninsula.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 43

Figure 29 (continued)

!60 cm

Matagorda

Day

/ :.... .'

.': .:"

..::.

Gulf

of

Mexico

IW1Id - to (11)1 t

N
44 NOAA Technical Report NMFS 110

IWlld - d (1) I

< 20 cm

Head-started - c (21)

Wild -d(14)

20 - 59.9 cm

Gulf

of

Mexico

Gulf

of

Mexico

t

N

t

N

Figure 30

Size distribution of Kemp's ridleys in region 5 - San Antonio Bay/Copano Bay/

Matagorda Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 45

Figure 30 (continued)

IWlld - A (5) I

160 cm

Gulf

of

Mextco t

N
27"30'

27"50' N

Gulf

of

Mexico

rted - [] (1) I IHead-stll _ A (17) t

Wild _ 0 (1) J IHistorical N

Corpus

Christi

Day

i""~' Ii . '...

.::

_~:;~;:~;;~N:MF~S;;1;10;~t:~_~7~c,=:~tr_~ 46 NOAA Teehoieal Report

< 20 em

Figure31 , . 'b tion of Kemp s Size dlstn u. 6 _Corpus . eglOn ridleys m r them Padre Christi Bay/Nor

Island.

t

N

Gulf

of

Mexico

d-c(ll) Head-starts _ li. (65) Wild

.:n to ,~/ . ':° 0 ':. :.: : ·0,. I :.~.

20 - 59,9 cm
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 47

Figure 31 (continued)

!60 em

Gulf

of

MexIco t

N

27°30'
48 NOAA Technical Report NMFS 110

IWild - Ii (2)1

< 20 cm

IWild - Ii 06>1

20 - 59.9 cm

"

PMre

Islaad

Gulf

of

Mexico

t

N

Ii

Gulf

of

MeXico

t

N

2MO'N

27"00'

Figure 32

Size distribution of Kemp's ridleys in region 7 - Central Laguna Madre/Padre

Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 49

Figure 32 (continued)

'Wild - A (12) I

~60 cm

A Gulf

of

MexIco

t

N

27000'
50 NOAA Technical Report NMFS 110

IWlld - t:. (1)1

< 20 cm

Gulf

of

Mexico

South

t:. Padre

Island

f

N

Gulf

of

Mexico

South

Padre

Island

26~O' N

Figure 33

Size distribution of Kemp's ridleys in region 8 - Southern

Laguna Madre/Padre Island.
Manzella and Williams: Distribution of Kemp's Ridley Sea Turtles 51

Figure 33 (continued)

.:.

GUlf

of

Mexico

tJ. South

~PDdre

tJ.lsland

160 cm
52 NOAA Technical Report NMFS 110

9~OO'

Texas

2

3

Gulf

of

Mexico

o

Head-started - 0 (I)

Wild - (I)

20 - 59.9 cm

t

N

Figure 34

Size distribution of Kemp's ridleys outside

the regional boundaries. The wild turtle

positioned on land near region 2 was

found in a drainage ditch in Houston, TX.